1. Field of the Invention
[0001] The present invention relates to new monomers and polymers and use of such polymers
as a resin binder component for photoresist compositions, particularly chemically-amplified
positive-acting resists that can be effectively imaged at short wavelengths such as
248 nm, 193 nm and 157 nm.
2. Background
[0002] Photoresists are photosensitive films used for transfer of images to a substrate.
A coating layer of a photoresist is formed on a substrate and the photoresist layer
is then exposed through a photomask to a source of activating radiation. The photomask
has areas that are opaque to activating radiation and other areas that are transparent
to activating radiation. Exposure to activating radiation provides a photoinduced
chemical transformation of the photoresist coating to thereby transfer the pattern
of the photomask to the photoresist-coated substrate. Following exposure, the photoresist
is developed to provide a relief image that permits selective processing of a substrate.
[0003] A photoresist can be either positive-acting or negative-acting. For most negative-acting
photoresists, those coating layer portions that are exposed to activating radiation
polymerize or crosslink in a reaction between a photoactive compound and polymerizable
reagents of the photoresist composition. Consequently, the exposed coating portions
are rendered less soluble in a developer solution than unexposed portions. For a positive-acting
photoresist, exposed portions are rendered more soluble in a developer solution while
areas not exposed remain comparatively less developer soluble.
[0004] In general, photoresist compositions comprise at least a resin binder component and
a photoactive agent. Photoresist compositions are described in Deforest,
Photoresist Materials and Processes, McGraw Hill Book Company, New York, ch. 2, 1975 and by Moreau,
Semiconductor Lithography, Principles, Practices and Materials, Plenum Press, New York, ch. 2 and 4, both incorporated herein by reference for their
teaching of photoresist compositions and methods of making and using the same.
[0005] More recently, chemically-amplified-type resists have been increasingly employed,
particularly for formation of sub-micron images and other high performance applications.
Such photoresists may be negative-acting or positive-acting and generally include
many crosslinking events (in the case of a negative-acting resist) or deprotection
reactions (in the case of a positive-acting resist) per unit of photogenerated acid.
In the case of positive chemically-amplified resists, certain cationic photoinitiators
have been used to induce cleavage of certain "blocking" groups pendant from a photoresist
binder, or cleavage of certain groups that comprise a photoresist binder backbone.
See, for example, U.S. Patents Nos. 5,075,199; 4,968,581; 4,883,740; 4,810,613; and
4,491,628, and Canadian Patent Application 2,001,384. Upon cleavage of the blocking
group through exposure of a coating layer of such a resist, a polar functional group
is formed, e.g., carboxyl or imide, which results in different solubility characteristics
in exposed and unexposed areas of the resist coating layer. See also R.D. Allen et
al.,
Proceedings of SPIE, 2724:334-343 (1996); and P. Trefonas et al.
Proceedings of the 11th International Conference on Photopolymers (Soc. Of Plastics Engineers), pp 44-58 (Oct. 6, 1997).
[0006] While currently available photoresists are suitable for many applications, current
resists also can exhibit significant shortcomings, particularly in high performance
applications such as formation of highly resolved sub-half micron and sub-quarter
micron features.
[0007] Consequently, interest has increased in photoresists that can be photoimaged with
short wavelength radiation, including exposure radiation of about 250 nm or less,
or even about 200 nm or less, such as wavelengths of about 248 nm (provided by KrF
laser) or 193 nm (provided by an ArF exposure tool). Use of such short exposure wavelengths
can enable formation of smaller features. Accordingly, a photoresist that yields well-resolved
images upon 248 nm or 193 nm exposure could enable formation of extremely small (e.g.
sub-0.25 µm) features that respond to constant industry demands for smaller dimension
circuit patterns, e.g. to provide greater circuit density and enhanced device performance.
[0008] However, many current photoresists are generally designed for imaging at relatively
higher wavelengths, such as I-line (365 nm) and G-line (436 nm) exposures and are
generally unsuitable for imaging at short wavelengths such as 193 nm and 248 nm. In
particular, prior resists exhibit poor resolution (if any image at all can be developed)
upon exposure to these shorter wavelengths. Among other things, current photoresists
can be highly opaque to extremely short exposure wavelengths such as 248 nm and 193
nm, thereby resulting in poorly resolved images. Efforts to enhance transparency for
short wavelength exposure can negatively impact other important performance properties
such as substrate adhesion, which in turn can dramatically compromise image resolution.
[0009] It thus would be desirable to have new photoresist compositions, particularly resist
compositions that can be imaged at short wavelengths such as 248 nm, 193 nm and 157
nm.
SUMMARY OF THE INVENTION
[0010] The present invention provides novel monomers and polymers and photoresist compositions
that comprise the polymers as a resin binder component.
[0011] The photoresist compositions of the invention can provide highly resolved relief
images upon exposure to extremely short wavelengths, particularly 248nm and 193 nm.
The photoresists of the invention preferably are chemically-amplified positive resists,
which utilize photoacid-induced cleavage of pendant alkyl ester polymer groups to
provide solubility differentials between exposed and unexposed areas of a resist coating
layer.
[0012] More particularly, norbornene carboxylate monomers in which the carboxylate functionality
is protected by (esterified with) photoacid-labile tertiary alicyclic groups. The
alicyclic group can comprise a single ring (e.g. cyclopentyl, cyclohexyl or cycloheptyl),
or may be polycyclic, e.g. and contain 2,3,4 or more bridged, fused or otherwise linked
rings. For instance, preferred monomers of the invention include compounds of the
following Formula I:
wherein R and R
1 are independently hydrogen, an ester moiety with a tertiary alicyclic group, optionally
substituted alkyl (including cycloalkyl) preferably-having from 1 to 16 carbons, optionally
substituted alkoxy preferably having from 1 to 16 carbons, optionally substituted
alkylthio preferably having from 1 to 16 carbons, and the like, with at least one
ofR and R
1 being an ester moiety with a tertiary alicyclic group. The one or two ester moieties
with tertiary alicyclic group may be directly pendant from the norbenene ring (i.e.
-C(=O)OR, where R is a tertiary alicyclic group), or the'ester moieties may be spaced
from the norbornene ring, e.g. by an optionally alkylene linkage (e.g., -(CH
2)
1-8C(=O)OR, where R is a tertiary alicyclic group). Preferably the one or two ester moieties
are directly pendant from the norbornene ring. Preferred tertiary alicyclic ester
R and R
1 groups of Formula I are shown below with reference to preferred X groups of Formula
II.
[0013] Particularly preferred monomers of the invention include compounds of the following
Formula II:
in which X of that Formula is a tertiary alicyclic group such as the following
groups, where the waved line indicates the chemical bond linkage to the norbornene
ester oxygen:
where in the above alicyclic structures R is an optionally substituted alkyl group,
particularly C
1-16 alkyl (including cycloalkyl), more typically C
1-6 alkyl; optionally substituted alkoxy group, particularly C
1-8 alkoxy, more typically C
1-6 alkoxy; or optionally substituted carbocyclic aryl, particularly optionally substituted
phenyl.
[0014] In general, polymers of the invention comprise one or more polymerized units of the
above discussed norbornene carboxylate monomers in which the carboxylate functionality
is protected by (esterified with) photoacid-labile tertiary alicyclic groups.
[0015] Preferred polymers of the invention contain other repeat units in addition to alicyclic-esterified
norbornene carboxylates. For example, preferred polymers may contain units provided
by polymerized electron-deficient monomers that may or may not be photoacid-labile,
such as an ethylene unsaturated ketone or di-ketone, e.g. an anhydride such as maleic
anhydride, itaconic anhydride, citrionic ahydride; amides such as maleimide; and esters,
particularly lactones.
[0016] Additional preferred polymers include those that contain a polymerized acrylate,
which may or may not be photoacid-labile. For example, photoacid-labile alkylesters
of acrylic acid, methacrylic acid and the like may be polymerized, e.g. t-butyl acrylate
or t-butyl methacrylate.
[0017] Polymers of the invention may contain other additional units. Additional photoacid-labile
groups are preferred in many instances. For example, polymers may contain additional
photoacid-labile groups such as pendant esters such as those of the formula -WC(=O)OR
5, wherein W is a linker such as a chemical bond, an alkylene particularly C
1-3 alkylene, or carbocyclic aryl such as phenyl, or aryloxy such as phenoxy, and R
5 is a suitable ester moiety such as an optionally substituted alkyl (including cycloalkyl)
suitably having from 1 to 20 carbons, more preferably 4 to 12 carbons, but without
a noncyclic or single ring alkyl group having 5 or more carbons and two or more secondary,
tertiary or quaternary carbons; optionally substituted alkenyl (including cycloalkenyl)
group suitably having from 2 to 20 carbons, more preferably about 4 to 12 carbons;
optionally substituted alkynyl group suitably having from 2 to 20 carbons, more preferably
about 4 to about 12 carbons; optionally substituted alkoxy group suitably having from
1 to 20 carbons, more preferably 2 to 12 carbons; or a heteroalicyclic group that
contains one or more N, O or S atoms and one or more rings having from 4 to 8 ring
members such as tetrahydrofuranyl, thienyl, tetrahydropyranyl, morpholino and the
like. Specifically preferred R
5 groups include e.g. t-butyl, tetrahydropyran, ethoxyethyl, or an alicyclic group
including bridged groups such as such as adamantyl including 2-methyl-2-adamantyl,
norbornyl, and isobornyl.
[0018] Polymers of the invention optionally may contain other groups that contribute to
aqueous developability of a photoresist. For example, preferred polymer groups that
contribute to aqueous developability contain carboxy or hydroxy moieties such as may
be provided by condensation of vinylaryl such as vinylphenol which may be provided
by condensation of vinylphenol, acrylic acid, methacrylic acid, 2-hydroxyethylmethacrylate,
or other hydrophilic monomers.
[0019] Other optional polymer units include those that may be provided by condensation of
a vinyl alicyclic group, e.g. 2-adamantyl-2-methyl methacrylate and isobomyl methacrylate,
or a non-cyclic alkyl group such as t-butyl methacrylate, or a vinyl nitrile such
as condensation of methacrylonitrile to provide pendant cyano groups. Pendant cyano,
acid (COOH), and/or alicyclic groups, such as those mentioned above, are often preferred
additional units of polymers of the invention.
[0020] For use in photoresists to be imaged at sub-200 nm wavelengths such as 193 nm, preferably
a polymer of the invention will be substantially free of any phenyl or other aromatic
groups. For example, preferred polymers contain less than 5 or 4 mole percent aromatic
groups, more preferably less than 1 mole percent aromatic groups, more preferably
less than 0.1, 0.02, 0.04 and 0.08 mole percent aromatic groups and still more preferably
less than 0.01 mole percent aromatic groups. Particularly preferred polymers are completely
free of aromatic groups. Aromatic groups can be highly absorbing of sub-200 nm radiation
and thus are undesirable for polymers used in photoresists imaged with such short
wavelength radiation.
[0021] The invention also provides methods for forming relief images, including methods
for forming a highly resolved relief image such as a pattern of lines where each line
has essentially vertical sidewalls and a line width of about 0.40 microns or less,
and even a width of 0.25, 0.20 or 0.16 microns or less. The invention further provides
articles of manufacture comprising substrates such as a microelectronic wafer substrate
or liquid crystal display or other flat panel display substrate having coated thereon
a polymer, photoresist or resist relief image of the invention.
[0022] The invention also includes novel methods for synthesis of monomers and polymers
of the invention. More specifically, methods are provided for synthesis of a norbomene
monomer substituted with a photoacid-labile group, including a tertiary alicyclic
ester, without isolation of any intermediates in a multiple-step synthesis.
[0023] More particularly, such monomer syntheses include e.g. reactions of, without isolation
of intermediates (one-pot synthesis):
1) addition/reduction reaction of an alicyclic ketone, typically with an alkylating
reagent such as a C1-8alkylating reagent such as Grignard reagent, particularly an alkyl-Grignard reagent
such as C1-8Mghalide, typically C1-8MgBr or C1-8MgCl;
2) reaction of the resulting endocyclic alcohol with a reactive α, β-unsaturated compound,
e.g. an acryloyl or methacryloyl halide, particularly acryloyl chloride or methacryloyl
chloride;
3) Diels-Alder reaction of the product of step 2), preferably with cyclopentadiene,
to provide a norbornene compound substituted with a photoacid-labile tertiary alicyclic
ester, including compounds of Formulae I or II above. Step 1) is not necessary if
an alicyclic alcohol is employed as a starting reagent.
[0024] Other aspects of the invention are disclosed infra.
DETAILED DESCRIPTION OF THE INVENTION
[0025] References herein to a "tertiary alicyclic ester group" or other similar term indicate
that a tertiary alicyclic ring carbon is covalently linked to the ester oxygen, i.e.
-C(=O)O-TR where T is a tertiary ring carbon of alicyclic group R. In at least many
cases, preferably a tertiary ring carbon of the alicyclic moiety will be covalently
linked to the ester oxygen, such as exemplified by the above depicted preferred alicyclic
moieties. However, the tertiary carbon linked to the ester oxygen also can be exocyclic
to the alicyclic ring, typically where the alicyclic ring is one of the substituents
of the exocyclic tertiary carbon. Typically, the tertiary carbon linked to the ester
oxygen will be substituted by the alicyclic ring itself, and/or one, two or three
alkyl groups having 1 to 12 carbons, more typically 1 to 8 carbon, even more typically
1, 2, 3, or 4 carbons. The alicyclic ring also preferably does not contain any aromatic
substitution.
[0026] As stated above, polymers of the invention comprise one or more repeat units of a
polymerized norbornene carboxylate esterified with photoacid-labile tertiary alicyclic
group. Preferred polymers of the invention comprise one or more polymerized repeat
units of compounds of Formula I and/or II as those formulae are defined above.
[0027] As discussed, various moieties, including moeties of compounds of Formulae I and/or
II may be optionally substituted. A "substituted" substituent may be substituted at
one or more available positions, typically 1, 2, or 3 positions by one or more suitable
groups such as e.g. halogen (particularly F, Cl or Br); C
1-8 alkyl; Cite alkoxy; C
2-8 alkenyl; C
2-8 alkynyl; hydroxyl; alkanoyl such as a C
1-6 alkanoyl e.g. acyl
[0028] Polymers of the invention can be prepared by a variety of methods. One suitable method
is free radical polymerization, e.g., by reaction of selected monomers to provide
the various units as discussed above in the presence of a radical initiator under
an inert atmosphere (e.g., N
2 or argon) and at elevated temperatures such as about 70°C or greater, although reaction
temperatures may vary depending on the reactivity of the particular reagents employed
and the boiling point of the reaction solvent (if a solvent is employed). Suitable
reaction solvents include e.g. tetrahydrofuran, ethyl lactate and the like. Suitable
reaction temperatures for any particular system can be readily determined empirically
by those skilled in the art based on the present disclosure. A variety of free radical
initiators may be employed. For example, azo compounds may be employed such as azo-bis-2,4-dimethylpentanenitrile.
Peroxides, peresters, peracids and persulfates also could be employed. See the examples
which follow for exemplary reagents and conditions for synthesis of polymers of the
invention.
[0029] Preferably a polymer of the invention will have a weight average molecular weight
(M
w) of 1,000 to 100,000, more preferably 2,000 to 30,000, still more preferably from
2,000 to 15,000 or 20,000, with a molecular weight distribution (M
w/M
n) of 3 or less, more preferably a molecular weight distribution of 2 or less. Molecular
weights (either M
w or M
n) of the polymers of the invention are suitably determined by gel permeation chromatography.
[0030] Polymers of the invention also may contain aromatic units, such as polymerized vinylphenol,
styrene units and the like. Such aromatic units are particularly suitable for polymers
used in photoresists imaged at 248 nm. However, as discussed above, for even shorter
wavelength imaging, such as 193 nm, preferably a polymer is substantially, essentially
or completely free of aromatic units.
[0031] Polymers of the invention used in photoresist formulations should contain a sufficient
amount of photogenerated acid labile ester groups to enable formation of resist relief
images as desired. For instance, suitable amount of such acid labile ester groups
will be at least 1 mole percent of total units of the polymer, more preferably 2 to
50 mole percent, still more typically 3 to 30 or 40 mole percent of total polymer
units. See the examples which follow for exemplary preferred polymers.
[0032] As discussed above, synthetic methods are provided to produce norbornene compounds
that contain a photoacid-labile moiety, including photoacid-labile tertiary alicyclic
esters. Preferred synthetic methods of the invention are exemplified by the following
Scheme:
[0033] Other examples:
[0034] As shown in the above Scheme, alicyclic ketone
1 (carbonyl being a ring member; tricyclodecan-8-one depicted in the Scheme) is reduced
to the related alcohol, preferably by in an addition reaction, particularly by reaction
with an alkylating reagent, preferably a Grignard reagent
2 to provide the tertiary alicyclic alcohol
3 (alcohol being a ring member). Such a Grignard reaction is preferably conducted under
reduced temperatures, particularly less than about 0°C, such as about -25°C. Preferably
the alicyclic ketone is added over time (e.g. over 0.5, 1, 2, 3 or 4 or more hours)
to a solution of the Grignard reagent maintained at reduced temperatures. The reaction
is preferably conducted in a suitable solvent, such as an aprotic solvent, e.g. THF.
Both the Grignard reagent and the alicyclic ketone can be admixed in such solvent.
After the addition of the alicyclic is complete, the reaction can be stirred, preferably
at somewhat elevated temperatures.
[0035] Thereafter, without isolation or other work-up of the addition reaction product
3, reactive α,β-unsaturated compound 4 is added directly to the reaction mixture that
contains tertiary alcohol
3. Preferably, the α,β-unsaturated compound
4 is added over time (e.g. over 0.5, 1,2, 3 or 4 or more hours) to a solution of the
reaction mixture that contains
3 that is at a reduced temperature, e.g. less than about 0°C, such as about -25°C.
Preferably, the reaction mixture is allowed to stir for an extended period (e.g. 2,
4, 6, 8, 10, 12, 14 or 16 hours or more) after the addition the α,β-unsaturated compound
4 is complete, and the reagents
3 and
4 can be allowed to warm from reduced temperature, e.g. to room temperature, to provide
the tertiary ester
5.
[0036] Thereafter, the reaction mixture that contains ester
5 can be directly (without isolation or other work-up of the addition reaction product
5), reacted (Diels-Alder) reaction with a diene, particularly cyclopentadiene, which
preferably is freshly cracked. After the diene addition is complete, preferably the
reaction mixture is stirred for an extended period, e.g. 10, 20, 30, 40, 50, 60, 70,
80 hours or more, and at an elevated temperature, e.g. at least about 40°C, 50°C,
or 60°C to provide the norbornene with tertiary alicyclic ester
7. The Scheme also shows other illustrative compounds
8 and
9 that can be prepared by similar route starting with adamantyl ketone and ethyl fenchol
respectively (synthesis starting with ethyl fenchol would omit alkylating reaction
with Grignard reagent). See the examples which follow for exemplary preferred reaction
conditions.
[0037] In the one-pot synthesis of the invention, preferably the reaction is conducted under
anhydrous conditions. Thus, for example, the reactions preferably proceed under an
inert atmosphere (N
2 or argon) and dry solvents are employed. As discussed above, the several reactions
of the one-pot synthesis proceed without any isolation or other work-up of reaction
products of any single stage of the synthesis.
[0038] Moreover, it has been found that this one-pot synthesis proceeds to provide a norbomene
monomer with photoacid-labile tertiary alicyclic ester (compound
7,
8 or
9 above) in high yields from a starting material of alicyclic ketone (compound
1 above). For instance, norbornene monomer with photoacid-labile tertiary alicyclic
ester (compound
7,
8 or
9 above) can be obtained in at least 30 or 40 percent yields from a starting material
of an alicyclic ketone (e.g. compound
1 above), or even higher yields such as at least 50, 60, 70, 75 or 80 percent yields
from a starting material of an alicyclic ketone (e.g. compound
1 above).
[0039] As discussed above, the polymers of the invention are highly useful as a resin binder
component in photoresist compositions, particularly chemically-amplified positive
resists. Photoresists of the invention in general comprise a photoactive component
and a resin binder component that comprises a polymer as described above.
[0040] The resin binder component should be used in an amount sufficient to render a coating
layer of the resist developable with an aqueous alkaline developer.
[0041] The resist compositions of the invention also comprise a photoacid generator (i.e.
"PAG") that is suitably employed in an amount sufficient to generate a latent image
in a coating layer of the resist upon exposure to activating radiation. Preferred
PAGs for imaging at 193 nm and 248 nm imaging include imidosulfonates such as compounds
of the following formula:
wherein R is camphor, adamantane, alkyl (e.g. C
1-12 alkyl) and perfluoroalkyl such as perfluoro(C
1-12alkyl), particularly perfluorooctanesulfonate and perfluorononanesulfonate. A specifically
preferred PAG is N-[(perfluorooctanesulfonyl)oxy]-5-norbornene-2,3-dicarboximide.
[0042] Sulfonate compounds are also suitable PAGs, particularly sulfonate salts. Two suitable
agents for 193 nm and 248 nm imaging are the following PAGS 1 and 2:
[0043] Such sulfonate compounds can be prepared as disclosed in European Patent Application
96118111.2 (publication number 0783136), which details the synthesis of above PAG1.
[0044] Also suitable are the above two iodonium compounds complexed with anions other than
the above-depicted camphorsulfonate groups. In particular, preferred anions include
those of the formula RSO
3 where R is adamantane, alkyl (e.g. C
1-12 alkyl) and perfluoroalkyl such as perfluoro (C
1-12alkyl), particularly perfluorooctanesulfonate, and perfluorobutanesulfonate.
[0045] Other known PAGS also may be employed in the resists of the invention. Particularly
for 193 nm imaging, generally preferred are PAGS that do not contain aromatic groups,
such as the above-mentioned imidosulfonates, in order to provide enhanced transparency.
[0046] A preferred optional additive of resists of the invention is an added base, particularly
tetrabutylammonium hydroxide (TBAH), or tetrabutylammonium lactate, which can enhance
resolution of a developed resist relief image. For resists imaged at 193 nm, a preferred
added base is a hindered amine such as diazabicyclo undecene or diazabicyclononene.
The added base is suitably used in relatively small amounts, e.g. 0.03 to 5 percent
by weight relative to the total solids.
[0047] Photoresists of the invention also may contain other optional materials. For example,
other optional additives include anti-striation agents, plasticizers, speed enhancers,
etc. Such optional additives typically will be present in minor concentrations in
a photoresist composition except for fillers and dyes which may be present in relatively
large concentrations, e.g., in amounts of from 5 to 30 percent by weight of the total
weight of a resist's dry components.
[0048] The compositions of the invention can be readily prepared by those skilled in the
art. For example, a photoresist composition of the invention can be prepared by dissolving
the components of the photoresist in a suitable solvent such as, for example, ethyl
lactate, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate,
propylene glycol monomethyl ether; propylene glycol monomethyl ether acetate and 3-ethoxyethyl
propionate. Typically, the solids content of the composition varies between 5 and
35 percent by weight of the total weight of the photoresist composition. The resin
binder and photoactive components should be present in amounts sufficient to provide
a film coating layer and formation of good quality latent and relief images. See the
examples which follow for exemplary preferred amounts of resist components.
[0049] The compositions of the invention are used in accordance with generally known procedures.
The liquid coating compositions of the invention are applied to a substrate such as
by spinning, dipping, roller coating or other conventional coating technique. When
spin coating, the solids content of the coating solution can be adjusted to provide
a desired film thickness based upon the specific spinning equipment utilized, the
viscosity of the solution, the speed of the spinner and the amount of time allowed
for spinning.
[0050] The resist compositions of the invention are suitably applied to substrates conventionally
used in processes involving coating with photoresists. For example, the composition
may be applied over silicon wafers or silicon wafers coated with silicon dioxide for
the production of microprocessors and other integrated circuit components. Aluminum-aluminum
oxide, gallium arsenide, ceramic, quartz, copper, and glass substrates are also suitably
employed.
[0051] Following coating of the photoresist onto a surface, it is dried by heating to remove
the solvent until preferably the photoresist coating is tack free. Thereafter, it
is imaged through a mask in conventional manner. The exposure is sufficient to effectively
activate the photoactive component of the photoresist system to produce a patterned
image in the resist coating layer and, more specifically, the exposure energy typically
ranges from 1 to 100 mJ/cm
2, dependent upon the exposure tool and the components of the photoresist composition.
[0052] As discussed above, coating layers of the resist compositions of the invention are
preferably photoactivated by a short exposure wavelength, particularly a sub-300 and
sub-200 nm exposure wavelength. Particularly preferred exposure wavelengths include
193 nm and 248 nm. However, the resist compositions of the invention also may be suitably
imaged at higher wavelengths. For example, a resin of the invention can be formulated
with an appropriate PAG and used as a chemically-amplified positive I-line resist,
i.e. a resist imaged at 365 nm.
[0053] Following exposure, the film layer of the composition is preferably baked at temperatures
ranging from 70°C to 160°C. Thereafter, the film is developed. The exposed resist
film is rendered positive working by employing a polar developer, preferably an aqueous
based developer such as quaternary ammonium hydroxide solutions such as a tetra-alkyl
ammonium hydroxide solution; various amine solutions preferably a 0.26 N tetramethylammonium
hydroxide, such as ethyl amine, n-propyl amine, diethyl amine, di-n-propyl amine,
triethyl amine, or methyldiethyl amine; alcohol amines such as diethanol amine or
triethanol amine; cyclic amines such as pyrrole, and pyridine. In general, development
is in accordance with procedures recognized in the art.
[0054] Following development of the photoresist coating over the substrate, the developed
substrate may be selectively processed on those areas bared of resist, for example
by chemically etching or plating substrate areas-bared of resist in accordance with
procedures known in the art. For the manufacture of microelectronic substrates, e.g.,
the manufacture of silicon dioxide wafers, suitable etchants include a gas etchant,
e.g. a chlorine or fluorine-based etchant such a Cl
2 or CF
4/CHF
3 etchant applied as a plasma stream. After such processing, resist may be removed
from the processed substrate using known stripping procedures.
[0055] All documents mentioned herein are incorporated herein by reference. The following
non-limiting examples are illustrative of the invention.
Examples 1-3: Syntheses of Monomers
Example 1: Norbornene ethyl tricyclodecane carboxylate monomer synthesis
[0056]
Material |
Amt (g) |
Amt (ml) |
Moles |
Source |
Tricyclodecan-8-one |
153.6 |
|
∼1.02 |
TCI |
Ethylmagnesiumchloride(25%) |
400 |
∼388 |
∼1.12 |
ACROS |
Acryloyl chloride |
108 |
∼96.9 |
∼1.19 |
Aldrich |
Tetrahydrofuran |
480 |
540 |
|
Aldrich |
Cyclopentadiene |
75 |
|
∼1.12 |
ACROS |
[0057] All reaction glassware was dried in the oven overnight at 100°C. The glassware was
set up and cooled under a stream of nitrogen. The reaction was carried out under a
blanket of nitrogen.
[0058] To a 2L flask fitted with a gas inlet, thermometer, overhead stirrer and a rubber
septum was added 400g of ethylmagnesium chloride, 25 wt% solution in tetrahydrofuran
(THE) via a double tipped needle using nitrogen pressure. The mixture was cooled to
-25 to -30°C using a dry ice/isopropanol bath. While the ethylmagnesium chloride solution
was cooling the 153.6g of tricyclodecan-8-one was dissolved in 480g of tetrahydrofuran.
To a 1L flask equipped with a gas inlet, glass stopper and a rubber septum was added
the 153.6g of tricyclodecan-8-one. The anhydrous, inhibitor free tetrahydrofuran was
transferred to the 1L flask via a double tipped needle using nitrogen pressure. When
the ethylmagnesium chloride was at -25 to -30°C, the tricyclodecan-8-one /THF solution
was transferred over a 2hr period to the 2L flask containing the ethylmagnesium chloride
via a double tipped needle using nitrogen pressure. The cooling bath was removed and
the reaction mixture was stirred for 2 hr. After stirring for 2 hr the mixture was
again cooled to -25 to -30°C using a dry ice/isopropanol bath. The acryloyl chloride
(108g) was then added dropwise over a 1.25 - 1.5 hour period using a 125ml pressure
equalizing dropping funnel. The reaction was allowed to come to room temperature with
overnight stirring. A white precipitate developed from the clear amber colored reaction
solution. After stirring overnight, freshly cracked cyclopentadiene (75g) was added
dropwise at room temperature over 30 minutes using a 125ml pressure equalizing dropping
funnel. The mixture was then heated for 68hr at 50°C. The reaction mixture was now
orange in color with a white precipitate present. The reaction was cooled to room
temperature. Water (DI) was added until all of the salts had dissolved (∼400ml) and
two distinct layer were seen. The layers were separated and the organic (upper) layer
was dried over magnesium sulfate. The THF was removed leaving 310g of an orange oil.
The orange oil was dissolved in 1.5L of hexane then washed with 1 X 500ml saturated
aqueous sodium bicarbonate solution and 2 X 500ml DI water. The layers were separated
and the organic layer dried over magnesium sulfate. The hexane was removed leaving
∼300g of an orange oil. The oil was distilled under reduced pressure (158°C/5mm) leaving
189g of pure norbornene ethyl tricyclodecane carboxylate.
Example 2: Synthesis of norbornene methyl tricyclodecane carboxylate
[0059]
[0060] A solution of 125 ml of 1.4 M methyl lithium (in ethyl ether) in 100 ml of hexane
was decanted into a three neck round-bottom flask at an ice-water bath. To it, a solution
of 24.00 g of tricyclo[5.2.1.0]decan-8-one in hexane was added dropwise. After addition,
the reaction mixture was stirred for 4 hours at 0°C. Then, a solution of 13 ml of
acroyl chloride in 50 ml of hexane was added dropwise at 0°C. After addition, the
reaction mixture was stirred at the same bath for overnight (16 hours). Next, 11 g
of cyclopentadiene in 50 mL of hexane was dropwise to the reaction mixture at ice/water
bath. After the addition, the ice/water bath was removed and the reaction mixture
was heated to 50°C for 48 hrs. During the periods, lots of white precipitation were
found. After filtering the white salts, the organic layer was washed with NaHCO
3 (sat aq) and water three times (3 x 300 ml). Then, the washed organic layer was dried
over anhydrous MgSO
4. The organic solvent was removed by a rotary pump to give the crude title monomer.
The monomer was purified by a reduced pressure (5 mmHg/154-158°C) to give the norbornene
methyltricyclodecane carboxylate (yields: 72%).
Example 3: Synthesis of Norbornene ethyl fenchol carboxylate
[0061]
[0062] A solution of 230 ml of 2.5 M n-butyl lithium in 50 ml of THF was decanted into a
three neck round-bottom flask at an ice-water bath. To it, a solution of 100 g of
ethyl fenchol in 50 ml THF was added dropwise. After addition, the reaction mixture
was stirred for 24 hours at 0°C. Then, a solution of 59.88 g of acroyl chloride in
150 ml of THE was added dropwise at 0°C. After addition, the reaction mixture was
stirred at the same bath for overnight (16 hours). Next, 40 g of cyclopentadiene in
50 mL of hexane was dropwise to the reaction mixture at ice/water bath. After the
addition, the ice/water bath was removed and the reaction mixture was heated to 50°C
for 48 hrs. During the periods, lots of white precipitation were found. After filtering
the white salts, the organic layer was washed with NaHCO
3 (sat aq) and water three times (3 x 300 ml). Then, the washed organic layer was dried
over anhydrous MgSO
4. The organic solvent was removed by a rotary pump to give the crude title monomer.
The monomer was purified by a reduced pressure (5 mmHg/145-148°C) to give the norbomene
ethylfenchol carboxylate (yields: 64%).
Examples 4-5: Polymer syntheses
Example 4: COMA terpolymer (molar ratio of norbornenelactone:norborneester:maleic
anhydride = 12.5/37.5/50)
[0063]
[0064] A mixture of Norbornene ethyltricyclodecane carboxylate (15.16 g), maleic anhydride
(6.60g), norbomene-spiro-butylactone (2.80 g), and V601 (0.31g, 1% mole of total monomers)
in 12.28 g ethylacetate was placed in a round-bottomed flask. After stirred for 5
minutes (until all solid were dissolved in the solvent), the flask was put into a
pre-heat 70°C oil bath. The reaction mixture was stirred at this temperature for 24
hours. After cooling, to this flask, 25.0 g of THF was added. The polymer was isolated
by precipitation into 1.5 L of hexane/IPA (1/1, %wt.). The suspension mixture was
stirred for 120 minutes. Then, the polymer was filtered off and washed the polymer
by additional 200 mL of hexane. The polymer was dried in a vacuum oven at 40 °C for
overnight (about 16 hours). Yield =25%.
Example 5: Tetrapolymer: norborene/(spiro-2-2-α-butyrolactone)-5-norborene/norbornene
ethyl tricyclodecane carboxylate /maleic anhydride (molar ratio of respective units:
7.5:7.5:35:50).
[0065]
[0066] Into a 100ml Round bottom flask the following was weighted out:
- Norbornene
- 1.22 grams (0.013 moles) (spiro-2-2-α-butyrolactone)-5-Norborene 2.13 grams (0.013
moles)
- Maleic Anhydride
- 8.86 grams (0.086 moles)
- Norbornene ethyl tricyclodecane carboxylate
- 18.18 grams (0.060 moles)
- V601
- 0.4 grams (0.0017 moles)
15 grams Ethyl acetate
[0067] A magnetic stir bar was added to the flask and the solution was stirred for ∼15 minutes
to dissolve the contents of the flask. Once in solution the flask was placed in a
hot oil bath that was preheated to 80°C. A condenser and N
2 line was attached on top and the reaction was allowed to stir for 24 hours. After
24 hours the heat was removed and the flask was allowed to cool to room temperature.
After cooling to room temperature the contents of the flask was precipitated into
1.5 L (of 50/50 hexanes/IPA w/w). The precipitated solution was stirred for 1.5 hours
and then the polymer was isolated, via a glass fretted funnel. The polymer was then
dried for 4 hours in the hood and then overnight in a vacuum oven, at room temperature.
This reaction yielded 15 grams / 30 grams of polymer, giving a 50% yield. This reaction
was later repeated at a 20gram scale and the oil bath heated to 90°C. This gave 11.21
grams /20 grams (56% yield).
Example 6: Photoresist preparation and lithographic processing
[0068] A photoresist of the invention is prepared by mixing the following components with
amounts expressed as weight percent based on total weight of the resist compositions:
Resist components |
Amount (wt.%) |
Resin binder |
15 |
Photoacid generator |
4 |
Ethyl lactate |
81 |
[0069] The resin binder is the polymer of Example 4 above. The photoacid generator is di-(4-t-butyl)iodonium(+/-)-10-camphor
sulfonate (PAG 1 above). Those resin and PAG components are admixed in the ethyl lactate
solvent.
[0070] The formulated resist composition is spin coated onto HMDS vapor primed 4 inch silicon
wafers and softbaked via a vacuum hotplate at 90°C for 60 seconds. The resist - coating
layer is exposed through a photomask at 193 nm, and then the exposed coating layers
are post-exposure baked at 110°C. The coated wafers are then treated with 0.26N aqueous
tetramethylammonium hydroxide solution to develop the imaged resist layer and provide
a relief image.
1. A method of preparation of a substituted norbornene compound comprising:
a) reacting an alicyclic alcohol with an α, β-unsaturated compound to provide an α,β-unsaturated
ester;
b) reacting the α,β-unsaturated ester with a diene to provide a norbornene compound,
wherein steps a) and b) are conducted without isolation of the α,β-unsaturated
ester prior to reaction with the diene.
2. The method of claim 1 wherein steps a) and b) are conducted in the same reaction vessel.
3. The method of claim 1 further comprising a step al) of reacting an alicyclic ketone
with an alkylating reagent to provide the alicyclic alcohol.
4. The method of claim 3 wherein steps al), a) and b) are conducted without isolation
of intermediate compounds.
5. The method of claim 4 wherein steps al), a) and b) are conducted in the same reaction
vessel.
6. The method of any one of claims 1 through 5 wherein the α,β-unsaturated is an acryloyl
halide or methacryloyl halide.
7. The method of any one of claims 1 through 6 wherein the diene is cyclopentadiene.
8. The method of any one of claims 1 through 7 wherein the steps al), a) and b) are conducted
under anhydrous conditions.
9. The method of any one of claims 1 through 8 wherein the norbornene compound is of
the following Formula I:
wherein R and R
1 are independently hydrogen, an ester moiety with a tertiary alicyclic group, optionally
substituted alkyl, optionally substituted alkoxy, with at least one of R and R
1 being an ester moiety with a tertiary alicyclic group.
10. The method of any one of claims 1 through 8 wherein the norbornene compound is of
the following Formula II:
wherein X is a tertiary alicyclic group.
11. A method of claim 9 or 10 wherein the alicyclic group corresponds to one of the following
structures:
wherein R" is optionally substituted alkyl, optionally substituted alkoxy, or
optionally substituted carobcyclic aryl.
12. A compound of the following Formula I:
wherein R and R
1 are independently hydrogen, an ester moiety with a tertiary alicyclic group, optionally
substituted alkyl, optionally substituted alkoxy, with at least one of R and R
1 being an ester moiety with a tertiary alicyclic group.
13. A compound of the following Formula II:
wherein X is a tertiary alicyclic group.
14. A compound of claim 12 or 13, obtainable by steps comprising:
a) reacting an alicyclic alcohol with an α, β-unsaturated compound to provide an α,β-unsaturated
ester;
b) reacting the α,β-unsaturated ester with a diene to provide a norbornene compound,
wherein steps a) and b) are conducted without isolation of the α,β-unsaturated ester
prior to reaction with the diene.
15. A polymer comprising repeat units of a polymerized monomer of the following Formula
I:
wherein R and R
1 are independently hydrogen, an ester moiety with a tertiary alicyclic group, optionally
substituted alkyl, optionally substituted alkoxy, with at least one of R and R
1 being an ester moiety with a tertiary alicyclic group.
16. A polymer comprising repeat units of a polymerized monomer of the following Formula
II:
wherein X is a tertiary alicyclic group.
17. A polymer of claim 15 or 16 wherein the monomer is obtainable by steps comprising:
a) reacting an alicyclic alcohol with an α, β-unsaturated compound to provide an α,β-unsaturated
ester;
b) reacting the α,β-unsaturated ester with a diene to provide a norbornene compound,
wherein steps a) and b) are conducted without isolation of the α,β-unsaturated ester
prior to reaction with the diene.
18. A positive-acting photoresist composition comprising a photoactive component and a
polymer of claims 15, 16 or 17.
19. The photoresist of claim 18 wherein the polymer comprises phenyl groups.
20. The photoresist of claim 18 wherein the polymer comprises less than about 1 mole percent
of aromatic groups.
21. The photoresist of claim 18 wherein the polymer is completely free of aromatic groups.
22. The photoresist of any one of claims 18 through 21 wherein the polymer further comprises
acrylate units.
23. The photoresist of claim 22 wherein the acrylate units comprise a photoacid-labile
moiety.
24. The photoresist of any one of claims 18 through 23 wherein the polymer further comprises
maleic anhydride units.
25. A method of forming a positive photoresist relief image, comprising:
(a) applying a coating layer of a photoresist of any one of claims 18 through 24 on
a substrate; and
(b) exposing and developing the photoresist layer to yield a relief image.
26. The method of claim 25 wherein the photoresist layer is exposed with radiation having
a wavelength of 193 nm.
27. The method of claim 25 wherein the photoresist layer is exposed with radiation having
a wavelength of 248 nm.
28. An article of manufacture comprising a microelectronic wafer substrate or flat panel
display substrate having coated thereon a layer of the photoresist composition of
any one of claims 18 through 24.
1. Verfahren zur Herstellung einer substituierten Norbornenverbindung, umfassend:
a) Reagieren eines alizyklischen Alkohols mit einer α, β-ungesättigten Verbindung,
um einen α, β-ungesättigten Ester bereitzustellen,
b) Reagieren des α, β-ungesättigten Esters mit einem Dien, um eine Norbornenverbindung
bereitzustellen,
worin die Schritte a) und b) ohne Isolierung des α, β-ungesättigten Esters vor der
Reaktion mit dem Dien durchgeführt werden.
2. Verfahren gemäß Anspruch 1, worin die Schritte a) und b) im gleichen Reaktionsgefäß
durchgeführt werden.
3. Verfahren gemäß Anspruch 1 ferner umfassend einen Schritt a1) Reagieren eines alizyklischen
Ketons mit einem Alkylierungsreagens, um den alizyklischen Alkohol bereitzustellen.
4. Verfahren gemäß Anspruch 3, worin die Schritte al), a) und b) ohne Isolierung von
Zwischenprodukten durchgeführt werden.
5. Verfahren gemäß Anspruch 4, worin die Schritte al), a) und b) im gleichen Reaktionsgefäß
durchgeführt werden.
6. Verfahren gemäß einem der Ansprüche 1-5, worin die α, β-ungesättigte Verbindung ein
Acryloylhalogenid oder Methacryloylhalogenid ist.
7. Verfahren gemäß einem der Ansprüche 1-6, worin das Dien Cyclopentadien ist.
8. Verfahren gemäß einem der Ansprüche 1-7, worin die Schritte al), a) und b) unter wasserfreien
Bedingungen durchgeführt werden.
9. Verfahren gemäß einem der Ansprüche 1-8, worin die Norbornenverbindung folgende Formel
I aufweist:
worin R und R
1 unabhängig voneinander Wasserstoff, eine Estereinheit mit einer tertiären alizyklischen
Gruppe, gegebenenfalls substituiertes Alkyl, gegebenenfalls substituiertes Alkoxy
sind, wobei mindestens einer von R und R
1 eine Estereinheit mit einer tertiären alizyklischen Gruppe ist.
10. Verfahren gemäß einem der Ansprüche 1-8, worin die Norbornenverbindung die folgende
Formel II aufweist:
worin X eine tertiäre alizyklische Gruppe ist.
11. Verfahren gemäß Anspruch 9 oder 10, worin die alizyklische Gruppe einer der folgenden
Strukturen entspricht:
worin R" gegebenenfalls substituiertes Alkyl, gegebenenfalls substituiertes Alkoxy
oder gegebenenfalls substituiertes carbozyklisches Aryl ist.
12. Verbindung mit der folgenden Formel I:
worin R und R
1 unabhängig voneinander Wasserstoff, eine Estereinheit mit einer tertiären alizyklischen
Gruppe, gegebenenfalls substituiertes Alkyl, gegebenenfalls substituiertes Alkoxy
sind, wobei mindestens einer von R und R
1 eine Estereinheit mit einer tertiären alizyklischen Gruppe ist.
13. Verbindung gemäß der folgenden Formel II:
worin X eine tertiäre alizyklische Gruppe ist.
14. Verbindung gemäß Anspruch 12 oder 13, erhältlich durch die Schritte, umfassend:
a) Reagieren eines alizyklischen Alkohols mit einer α, β-ungesättigten Verbindung,
um einen α, β-ungesättigten Ester bereitzustellen
b) Reagieren des α, β-ungesättigten Esters mit einem Dien, um eine Norbornenverbindung
bereitzustellen,
worin die Schritte a) und b) ohne Isolierung des α, β-ungesättigtem Esters vor der
Reaktion mit dem Dien durchgeführt werden.
15. Polymer umfassend Wiederholungseinheiten eines polymerisierten Monomers der folgenden
Formel I:
worin R und R
1 unabhängig voneinander Wasserstoff, eine Estereinheit mit einer tertiären alizyklischen
Gruppe, gegebenenfalls substituiertes Alkyl, gegebenenfalls substituiertes Alkoxy
sind, wobei wenigstens einer von R und R
1 eine Estereinheit mit einer tertiären alizyklischen Gruppe ist.
16. Polymer umfassend Wiederholungseinheiten eines polymerisierten Monomers der folgenden
Formel II:
worin X eine tertiäre alizyklische Gruppe ist.
17. Polymer gemäß Anspruch 15 oder 16, worin das Monomer erhältlich ist durch die Schritte,
umfassend:
a) Reagieren eines alizyklischen Alkohols mit einer α, β-ungesättigten Verbindung,
um einen α, β-ungesättigten Ester bereitzustellen,
b) Reagieren des α, β-ungesättigten Esters mit einem Dien, um eine Norbornenverbindung
bereitzustellen,
worin die Schritte a) und b) ohne Isolierung des α, β-ungesättigten Esters vor der
Reaktion mit dem Dien durchgeführt werden.
18. Positiv wirkende Photoresistzusammensetzung, umfassend eine photoaktive Komponente
und ein Polymer gemäß den Ansprüchen 15, 16 oder 17.
19. Photoresist gemäß Anspruch 18, worin das Polymer Phenylgruppen umfasst.
20. Photoresist gemäß Anspruch 18, worin das Polymer weniger als etwa ein Mol Prozent
aromatischer Gruppen umfasst.
21. Photoresist gemäß Anspruch 18, worin das Polymer völlig frei von aromatischen Gruppen
ist.
22. Photoresist gemäß einem der Ansprüche 18-21, worin das Polymer ferner Acrylateinheiten
umfasst.
23. Photoresist gemäß Anspruch 22, worin die Acrylateinheiten eine Photosäurelabile Einheit
umfassen.
24. Photoresist gemäß einem der Ansprüche 18- 23, worin das Polymer ferner Maleinsäureanhydrid-Einheiten
umfasst.
25. Verfahren zum Formen eines positiven Photoresist-Reliefbildes, umfassend:
a) Aufbringen einer Beschichtungslage eines Photoresists gemäß einem der Ansprüche
18-24 auf einem Substrat, und
b) Aussetzen und Entwickeln der Photoresistschicht, um ein Reliefbild zu erhalten.
26. Verfahren gemäß Anspruch 25, worin die Photoresistschicht einer Strahlung ausgesetzt
wird, die eine Wellenlänge von 193 nm aufweist.
27. Verfahren gemäß Anspruch 25, worin die Photoresistschicht einer Strahlung ausgesetzt
wird, die eine Wellenlänge von 248 nm aufweist.
28. Hergestellter Artikel umfassend ein mikroelektronisches Wafersubstrat oder ein Flachbildschirmsubstrat,
welches darauf eine Schicht einer Photoresistzusammensetzung gemäß einem der Ansprüche
18-24 beschichtet aufweist.
1. Procédé de préparation d'un composé de norbomène substitué, comprenant :
a) la réaction d'un alcool alicyclique avec un composé α,β-insaturé pour donner un
ester α,β-insaturé;
b) la réaction de l'ester α,β-insaturé avec un diène pour donner un norbomène,
dans lequel les étapes a) et b) sont mises en oeuvre sans isolement de l'ester α,β-insaturé
avant la réaction avec le diène.
2. Procédé selon la revendication 1, dans lequel les étapes a) et b) sont mises en oeuvre
dans le même récipient réactionnel.
3. Procédé selon la revendication 1, qui comprend en outre une étape a1) de réaction
d'une cétone alicyclique avec un réactif d'alkylation pour donner l'alcool alicyclique.
4. Procédé selon la revendication 3, dans lequel les étapes a1), a) et b) sont mises
en oeuvre sans isolement des composés intermédiaires.
5. Procédé selon la revendication 4, dans lequel les étapes a1), a) et b) sont mises
en oeuvre dans le même récipient réactionnel.
6. Procédé selon l'une quelconque des revendications 1 à 5, dans lequel le composé α,β-insaturé
est un halogénure d'acryloyle ou un halogénure de méthacryloyle.
7. Procédé selon l'une quelconque des revendications 1 à 6, dans lequel le diène est
le cyclopentadiène.
8. Procédé selon l'une quelconque des revendications 1 à 7, dans lequel les étapes a1),
a) et b) sont mises en oeuvre dans des conditions anhydres.
9. Procédé selon l'une quelconque des revendications 1 à 8, dans lequel le composé de
norbornène a la formule I ci-après :
dans laquelle R et R
1 représentent indépendamment un atome d'hydrogène, un fragment ester ayant un groupe
alicyclique tertiaire, un groupe alkyle éventuellement substitué, alcoxy éventuellement
substitué, au moins l'un des radicaux R et R
1 étant un fragment ester ayant un groupe alicyclique tertiaire.
10. Procédé selon l'une quelconque des revendications 1 à 8, dans lequel le composé de
norbomène a la formule II ci-après :
dans laquelle X est un groupe alicyclique tertiaire.
11. Procédé selon la revendication 9 ou 10, dans lequel le groupe alicyclique correspond
à l'une des formules suivantes :
où R" est un groupe alkyle éventuellement substitué, alcoxy éventuellement substitué
ou aryle carbocyclique éventuellement substitué.
12. Composé ayant la formule I ci-après :
dans laquelle R et R
1 représentent indépendamment un atome d'hydrogène, un fragment ester ayant un groupe
alicyclique tertiaire, un groupe alkyle éventuellement substitué, alcoxy éventuellement
substitué, au moins l'un des radicaux R et R
1 étant un fragment ester ayant un groupe alicyclique tertiaire.
13. Composé ayant la formule II ci-après :
dans laquelle X est un groupe alicyclique tertiaire.
14. Composé selon la revendication 12 ou 13, pouvant être obtenu par les étapes comprenant
:
a) la réaction d'un alcool alicyclique avec un composé α,β-insaturé pour donner un
ester α,β-insaturé ;
b) la réaction de l'ester α,β-insaturé avec un diène pour donner un composé de norbornène,
dans lequel les étapes a) et b) sont mises en oeuvre sans isolement de l'ester
α,β-insaturé avant la réaction avec le diène.
15. Polymère comprenant des motifs répétitifs d'un monomère polymérisé ayant la formule
I ci-après :
dans laquelle R et R
1 représentent indépendamment un atome d'hydrogène, un fragment ester ayant un groupe
alicyclique tertiaire, un groupe alkyle éventuellement substitué, alcoxy éventuellement
substitué, au moins l'un des radicaux R et R
1 étant un fragment ester ayant un groupe alicyclique tertiaire.
16. Polymère comprenant des motifs répétitifs d'un monomère polymérisé ayant la formule
II ci-après :
dans laquelle X est un groupe alicyclique tertiaire.
17. Polymère selon la revendication 15 ou 16, dans lequel le monomère peut être obtenu
par les étapes comprenant :
a) la réaction d'un alcool alicyclique avec un composé α,β-insaturé pour donner un
ester α,β-insaturé;
b) la réaction de l'ester α,β-insaturé avec un diène pour donner un norbornène,
dans lequel les étapes a) et b) sont mises en oeuvre sans isolement de l'ester
α,β-insaturé avant la réaction avec le diène.
18. Composition de réserve photosensible à action positive, comprenant un composant photoactif
et un polymère selon les revendications 15, 16 ou 17.
19. Réserve photosensible selon la revendication 18, dans laquelle le polymère comprend
des groupes phényle.
20. Réserve photosensible selon la revendication 18, dans laquelle le polymère comprend
moins d'environ 1 % en moles de groupes aromatiques.
21. Réserve photosensible selon la revendication 18, dans laquelle le polymère est entièrement
exempt de groupes aromatiques.
22. Réserve photosensible selon l'une quelconque des revendications 18 à 21, dans laquelle
le polymère comprend en outre des motifs acrylate.
23. Réserve photosensible selon la revendication 22, dans laquelle les motifs acrylate
comprennent un fragment labile vis-à-vis des photoacides.
24. Réserve photosensible selon l'une quelconque des revendications 18 à 23, dans laquelle
le polymère comprend en outre des motifs anhydride maléique.
25. Procédé de formation d'une image en relief à effet de réserve photosensible positive,
qui comprend :
(a) l'application d'une couche de revêtement d'une réserve photosensible selon l'une
quelconque des revendications 18 à 24 sur un substrat ; et
(b) l'exposition et le développement de la couche de réserve photosensible pour donner
une image en relief.
26. Procédé selon la revendication 25, dans lequel la couche de réserve photosensible
est exposée à un rayonnement ayant une longueur d'onde de 193 nm.
27. Procédé selon la revendication 25, dans lequel la couche de réserve photosensible
est exposée à un rayonnement ayant une longueur d'onde de 248 nm.
28. Article de manufacture, comprenant un substrat de pastille microélectronique ou un
substrat pour affichage par écran plat, qui est revêtu d'une couche de la composition
de réserve photosensible selon l'une quelconque des revendications 18 à 24.